I'm joined now by my colleague on the NPR Ed Team, Cory Turner. He's done most of our Common Core reporting, and he edited this postcard series. Cory, thanks for coming in.

CORY TURNER, BYLINE: Thanks for having me, Eric.

WESTERVELT: Cory, the Common Core standards aren't that new but there's a lot of misconceptions out there about them. What are the big ones for you?

TURNER: I'll start out with uniformity. It's in the name. It's totally understandable that people hear Common Core and assume that what's happening in one classroom is happening in every classroom. But what people don't realize is that the Core are standards, they're not curriculum. They don't come with lesson plans or textbooks. Teachers are large doing this themselves as they always have. So just because - let's say a fifth-grade teacher in Louisville, like we just heard, decides Minecraft is a great way to get his kids using grids. Well, that doesn't mean that teachers everywhere else are doing the exact same thing.

WESTERVELT: Another criticism we hear across the political spectrum, Cory, is that the Common Core has created an ever more toxic testing environment. That kids are simply taking tests, you know, all the time now. I mean, do they have a point?

TURNER: Yeah, you know. Lots of folks who don't follow education, don't realize that this requirement, that states test kids once a year. That started more than a decade ago with No Child Left Behind enacted in 2002 under President George W. Bush. And No Child is still the law of the land. Schools do it so they can get federal Title I dollars and again because the Common Core are standards. States realizing under No Child Left Behind, they had to still test their kids, they needed to make new tests that are aligned to the Core. But the idea is -and this is generally what we expect to see next year, is all of these new that are aligned to the Core will simply replace all of the old state tests. So technically no additional tests for the Common Core.

WESTERVELT: So it's built on the testing regimes started under No Child Left Behind, but it doesn't necessarily mean an increase in testing, correct?

TURNER: For the most part, yes. Next year - again kids should not be taking extra tests. But I do have to say, there have been real growing pains this year. I recently spoke with a mother in Montgomery County, Maryland who was really angry about her daughter's algebra final. What happened is - and I'm going to try to keep this simple. This past year was the first year that the county's algebra curriculum was aligned to the Common Core and so was the algebra final exam that the district wrote, again aligned to the Common Core, OK. But at the same time - because they haven't phased completely in the Common Core, kids in the district were still required to take the old Maryland State end of year test. And what happened is teachers realized about three weeks before the end of the year that there were a lot of math concepts on this big state test that aren't in the Core. And so teachers started cramming in these concepts, trying to teach the kid what they need to do well on this test. And ultimately, what happened is when the kids came around to take that Common Core Algebra final, they bombed it. Eighty-two percent failure rate among high school kids in the district. It was so bad that the district actually applied a 15-point curve and had to delay report cards.

WESTERVELT: Wow. Eighty-two percent of high schoolers failed. I mean, doesn't that underscore how, sort of chaotic and hard implementation of these standards will be?

TURNER: I think it is, at least to a certain extent, it's hard to know where else this may have happened or may be happening. But let's face it, adopting new standards and implementing new standards, it's a really tough thing, especially when you find yourself straddling two worlds, old state tests that you still have to administer and new Common Core tests that you're phasing in. It's hard to know if we'll be hearing the same stories next year. We'll just have to see.